1. Field of the Invention
The present invention relates to antenna arrays in general and, more particularly, to a delay line antenna array system.
2. Description of the Related Art
Antenna arrays have advantages over single, omnidirectional antennas due to three general characterisitics of antenna arrays. First, antenna arrays provide a signal-to-noise ratio (SNR) gain equal to the number of antennas. Second, antenna arrays can reduce multipath delay spread and fading fluctuations of the received signal because the antenna array can focus on the reception of one or more strong path signals with low relative delays while signals with large excess delays can be attenuated. Third, antenna arrays can separate signals from different users transmitting at the same frequency. These three characteristics for antenna arrays enhance the capacity of wireless, indoor and outdoor networks.
A disadvantage associated with antenna arrays is complexity. Multiple receivers are needed, one for each antenna, and existing methods of combining the different antenna signals are rather complicated and costly. For example, if the different antenna signals are combined digitally, analog-to digital converters are required for the different antennas. Accordingly, an antenna array system is needed which provides the advantages associated with antenna arrays while reducing the complexity and costs of current antenna array systems.